3,153 research outputs found

    The Effect of Social Media on Iranian Citizens’ Electoral Participation and Political Action

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    The present age is called the age of communication. Undoubtedly, in all matters of the world, the most incredible information is on the shoulders of the mass media. Today, the media have influenced the identity of contemporary man by expanding geographical, cultural and political boundaries so that the identity of modern man can be called media identity. The increasing role of new means of mass communication in various parts of human life has led to multiple fields. One area that social media have influenced in the present age is political participation. The present paper sought to test the effect of social media on the Iranian citizens’ willingness to electoral participation political actions using the World Values Survey (WVS) wave 7 data release (49 countries/territories). The results show that social media indirectly, through the mediator variable of political trust, reduces the willingness of individuals to participate in elections. Moreover, the results show that social media, both directly and indirectly, increases citizens’ willingness to engage in political protests

    The Enzymatic Activity and Molecular Characterization of a Secreted Subtilisin-Like Protease in Microsporum gypseum and Trichophyton vanbreuseghemii

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    Background: Subtilisin -like proteases are the group of proteases including keratinases found in dermatophytes which de­graded keratin. Determination of the proteases activity of Trichophyton vanbreuseghemii isolates which were obtained from soil and clinical and soil isolates of Microsporum gypseum in Iran and characterization of their genome were aim of present study.Methods: Ezymatic activity was determined by use of chromogenic substrates. The genes, which coded subtilisin-like pro­teases in above-mentioned dermatophytes, was identified and amplified by using specific primers in PCR. Results: The highest yield of enzyme production was observed in only one isolate of T. vanbreuseghemii Ir-84 whereas low enzyme activity was observed in M. gypseum isolates. Homology study of obtained nucleotide as well as amino acid sequences indicated different rates of homology with other subtilisin-like proteases genes in other pathogenic dermato­phytes. Conclusion: Intra-strain differences were observed in production of serine proteinases and molecular characterization of genes encoding such enzymes could be of great interest for studies on pathogenicity and other purposes

    Study of chemical and physical behavior cotton fabrics treated by corona discharge after several laundering

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    Cotton fabric because of finishing process has shrinkage behavior after laundering and for improving this problem, chemical agents utilize for anti-shrinkage. This temporary finishing can reduce shrinkagebut has many environmental problems. Corona discharge treatment has been used for cotton fabric, other fibers and polymers. This treatment can reduce costs and environmental impacts. In this study, cotton fabric was treated by corona discharge instrument at 2 - 40 passages and fabrics were washed with laundering method. After four times laundering, shrinkage behavior of corona discharge treated fabric as compared with un-treated fabric decrease. After 10 passages of corona discharge treatment,water, dye absorption and shrinkage are modified but after 14 passages, despite of shrinkage improvement, dyeing properties decrease

    The Lateral Migration of a Drop under Gravity between Two Parallel Plates at Finite Reynolds Numbers

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    A finite difference / front tracking method is used to examine the lateral migration of a three-dimensional deformable drop in plane Poiseuille flow at a finite-Reynolds-number. The computations are based on an improved implementation of the front tracking method at finite Reynolds numbers that include convective terms. The elliptic pressure equation is solved by a multigrid method. Both neutrally buoyant and non-neutrally buoyant drop are studied. The computation is performed within a unit cell which is periodic in the direction along the channel. A neutrally buoyant drop lags the fluid slightly, and the wall effect balances the effect of the curvature of the velocity profile, giving rise to an equilibrium lateral position about halfway between the wall and the centerline (the Segre- Silberberg effect). Results are presented over a range of density ratios. In the non-neutrally buoyant case, the gravity force is imposed along the flow direction. Non-neutrally buoyant drops have more complicated patterns of migration, depending upon the magnitude of the buoyancy force. When the density difference is small, the equilibrium position is either near the wall or near the centerline, depending on whether the drop leads or lags the local fluid. When the density difference is large enough, the equilibrium position shifts towards the centerline, irrespective of whether the drop is lighter or heavier than the fluid. The effect of Reynolds number and capillary number on the non-neutrally buoyant drops is investigated. The accuracy of the method is assessed by comparison with the other simulations and experiments

    Flow Pattern Analysis and Performance Improvement of Regenerative Flow Pump Using Blade Geometry Modification

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    Regenerative pump is a low specific speed and rotor-dynamic turbomachine capable of developing high heads at low flow rates. In this paper, a numerical study has been carried out in order to investigate the effect of blade angle on the performance of a regenerative pump. Two groups of impellers were employed. The first type has symmetric angle blades with identical inlet/outlet angles of ±10°, ±30°, and ±50° and the second group has nonsymmetric angle blades in which the inlet angle was set to 0° and six different angles of ±10°, ±30°, and ±50° were designed for the outlet of the blades. A total of 12 impellers, as well as primary radial blades impeller, were investigated in this study. The results showed that all forward blades have higher head coefficients than radial blades impeller at design flow coefficient. It was found that regenerative pumps with symmetric angle forward blades have better performance than other types. Also, it is worth mentioning that the highest head coefficient and efficiency occur at angle +10<β<+30 of symmetric angle blades. It was found that the maximum efficiency occurs at angle of +15.5° by curve fitting to the data obtained from numerical simulations for symmetric angle forward blades

    Biology and population dynamics of Scaeva albomaculata (Diptera: Syrphidae) in almond orchards of Shahrekord, Iran

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    Biology of Scaeva albomaculata (Macquart) was investigated on Brachycaudus amygdalinus (Schouteden) as a prey in laboratory conditions (20 ± 2 ºC and 45 ± 5 % RH). Developmental times were 2.57 ± 0.098, 1.57 ± 0.072 and 4.3 ± 0.085 days for the first, second and third instar larvae, respectively. The first and second instar larvae of syrphid fly consumed 21.7 ± 0.87 and 35.1 ± 1.25 the first and second nymphs, respectively, whereas the third instar larvae consumed 613.2 ± 18.43 alate nymphs of B. amygdalinus. Adults of syrphid flies mostly emerged in early morning. Population dynamics of eggs and larvae and larval behavior were studied from emergence time (early March) to late October during 2001-2004 in two regions (Shahrekord and Shorab-Saghir). In natural conditions, the larvae that completed their growth left the almond twigs and pupated at a depth of 3-5 cm below the soil surface. The most important natural enemies of S. albomaculata larvae were identified as Diplazon laetatorius (Fabricius) (Hym.: Ichneomonidae) and Dotriothorax sp. (Hym.: Encyrtidae), which parasitized 34% and 5% of the larvae, respectively. These parasitoids emerged from pupae of S. albomaculata. Another mortality agent was an unknown pathogen, which caused the body content of the pupae to become a milky liquid

    VINYL: The VIrtual Neutron and x-raY Laboratory and its applications

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    Experiments conducted in large scientific research infrastructures, such as synchrotrons, free electron lasers and neutron sources become increasingly complex. Such experiments, often investigating complex physical systems, are usually performed under strict time limitations and may depend critically on experimental parameters. To prepare and analyze these complex experiments, a virtual laboratory which provides start-to-end simulation tools can help experimenters predict experimental results under real or close to real instrument conditions. As a part of the PaNOSC (Photon and Neutron Open Science Cloud) project, the VIrtual Neutron and x-raY Laboratory (VINYL) is designed to be a cloud service framework to implement start-to-end simulations for those scientific facilities. In this paper, we present an introduction of the virtual laboratory framework and discuss its applications to the design and optimization of experiment setups as well as the estimation of experimental artifacts in an X-ray experiment

    Genomic catastrophes frequently arise in esophageal adenocarcinoma and drive tumorigenesis

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    Oesophageal adenocarcinoma (EAC) incidence is rapidly increasing in Western countries. A better understanding of EAC underpins efforts to improve early detection and treatment outcomes. While large EAC exome sequencing efforts to date have found recurrent loss-offunction mutations, oncogenic driving events have been underrepresented. Here we use a combination of whole-genome sequencing (WGS) and single-nucleotide polymorphism-array profiling to show that genomic catastrophes are frequent in EAC, with almost a third (32%, n¼40/123) undergoing chromothriptic events. WGS of 22 EAC cases show that catastrophes may lead to oncogene amplification through chromothripsis-derived double-minute chromosome formation (MYC and MDM2) or breakage-fusion-bridge (KRAS, MDM2 and RFC3). Telomere shortening is more prominent in EACs bearing localized complex rearrangements. Mutational signature analysis also confirms that extreme genomic instability in EAC can be driven by somatic BRCA2 mutations. These findings suggest that genomic catastrophes have a significant role in the malignant transformation of EAC

    The effectiveness of integrating educational robotic activities into higher education Computer Science curricula: a case study in a developing country

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    In this paper, we present a case study to investigate the effects of educational robotics on a formal undergraduate Computer Science education in a developing country. The key contributions of this paper include a longitudinal study design, spanning the whole duration of one taught course, and its focus on continually assessing the effectiveness and the impact of robotic-based exercises. The study assessed the students' motivation, engagement and level of understanding in learning general computer programming. The survey results indicate that there are benefits which can be gained from such activities and educational robotics is a promising tool in developing engaging study curricula. We hope that our experience from this study together with the free materials and data available for download will be beneficial to other practitioners working with educational robotics in different parts of the world
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